You can offer the services related to your skills and ask payment in Bitcoins.

If you have some money to invest, you can buy bitcoin and let it grow over time.
For buying guide check here.

You can also earn free Bitcoins through faucets though the amount will be very small, join many faucets to increase earning, a lot of faucets are scam so please check before registering in any one of them if they are authentic or not.

E.g of faucets- Freebitco, join here.

Hope it helps